This work researches the process of plastic injection molding and construction development of injection mold for final product, which is wall plug. Required material used for the product is polypropylene, which is suitable for injection molding. The tool construction must meet all the necessary requirements and ensure optimum and smooth operation. The type of tool was selected on the basis of products’ geometry, while the choice of certain systems within the tool was determined by economic and technical criteria. We also included the implementation of injection molding simulations, in order to verify the suitability of the product, tool and selected systems.